Imazamox is a systemic herbicide that functions by inhibiting the acetolactate synthase (ALS) protein in plants. The compound di alkyl-5,6 dicarboxylate-3-alkoxymethyl pyridine of formula (I)

is an important intermediate for preparing the herbicidal active ingredient Imazamox (2-[(RS)-4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl]-5-methoxymethylnicotinic acid).
Different manufacturing processes are known from the literature. EP0548532 discloses the reaction of methyl pyridine with halogenating agent to minimize the dihalogenated product and the reaction of ammonium bromide in methanol under nitrogen reflux for 6 hours. U.S. Pat. No. 5,760,239 discloses preparing 2, 3-disubstituted 5-methoxymethyl pyridine by reacting the ammonium bromide with base in presence of an alcohol at temperature of 120-180° C. and under pressure in closed system. WO 2010066669 describes preparing 2, 3 disubstituted 5-methoxymethyl pyridine from trimethyl ammonium bromide, dimethyl ester in methanol/H2O with base comprising MOCH3, MOH, where the reaction is under pressure in closed vessel at temperature of from 75 to 110° C. WO 2010055139 discloses preparing 2,3-disubstituted 5-pyridylmethyl ammonium bromide from 2, 3 disubstituted 5-pyridylmethyl reacts with bromine followed with trialkyl amine.
However, there is a need to develop a more efficient synthesis pathway by improving the different steps of the process and there is a need to improve each step of the complete reaction in high yield and conversion.